Thermostatic circuit-controller.



G.E.SPBAR. THBRMOSTATIG CIRGUXT CONTROLLER. APPLICATION FILED APR.11,1913.

1,115,607. Patented 1ma;11g/1:21'.4 17259.11;

representing like parts.-

' 2o constant temperature.

A lment embed in so 4the arrow.

-unirnn sTArn-s PATENT naaien.

GEORGE E. srEAn, or 'Aivinsnunin MASSACHUSETTS, AssreNonTo sTaNnAryn'reen MoMETEn COMPANY, or BOSTON, MASSACHUSETTS, A ConronATioN or MAINE.

TTHERMOSTATIC CIRCUIT-CGNTROLLER.

Patented Nov. 3, 1914,

T'o all whom it maylconcemt Be it known that I, GEORGE E. SPEAn, 'a lcitizen of the United States, residing in Amesbury, county of Essex, andState of 5 Massachusetts, have invented an Improvement in ThermostaticCircuit-Controllers, of which 'the following description, in connectionwith theaccompanyingdrawings, is`

a specificatiomlike `letters on the drawings This inventionelates to athermostatic j circuit controller, especially adapted for and closing ofthe controlling the opcnin p hot water. heaters,

dampers of 4steam an 15 furnaces andthe like', and has for its object toprovides simple, conipact, .eiiicient and inexpensiveapparatus withwhich the temperature of-a ouse or other building may be regulated andmaintained at a substantially The particular features of the inventionvFigure 1l is a front elevation of an instrul this y invention. likeviewlwit t ecovcr andglass removed. Fig;` 3, an enlirged.vepticalsectionon the 'line 3 3, Fig. (1. Fig. 4, erection-ion `the linefil-4, Fi 3, Alooking in the direction of ig 51, a' rear elevation .ofthe instrument, andl Fig. 6, a diagram of circuits to illustrate theWorkingof the instrument.

The' instrument hereinshown as embodyin -this invention 'is providedwith a circu ar casing a having a covei'fbf4 rovided with a slotc behindwhich i iocate a glass disk d. The casing e conta As e, mtal disk esuitably secured in fixed osition within it and'provided with a curveslot f and above the latter with a' scale or series of graduations gindicative of degrees ofitemperatlire..

In the present instance, the dish:A e is' positioned within the casingby Vstuds It secured to the rear wall of the casing and a ring i,

which bears against the 'front face of the disk.V The ring j isretainedwithin the casingby the glass disk (Z and cover. b. The metaldisk c di'ides the casing into two chambers m, n, and has secured to itsreal" side a plate 12 and ayoke 13, which support a shaft 14, which isdesigned to be turnedin opposite directions by a coiled thermostaticstrip 16 whose eonvolutions are concentric, and which has one endattached to the shaft 14;v and its other end to a stud 17 Fig. 2, a.

onthefplate 12, The shaft 14 is extended through a1 holein the disk einto the chamber fm, and has attached to its front end a contact erin ormember 20, whose upperk end'. 1sV extended between two circuit terminalsShown asset screws 21, 22, which are adjustably carriedzby studs 23,24on the cross bar its lower end a disk 30 provided with a plurality ofgear teeth 31, which mesh with a p inion 32 on a shaft 33, supported bythe disk ev and by a cross bar 34 secured thereto as by screws 35. Thedisk 30 is mounted to turn on a hub 37 attached to the plate 12 andprojected through a hole in the disk e, and lis retained on t e hub by awasher 38. The shaft 33 is turned by a handle 40, which is preferablydetachable from the said shaft,`

and to this end is provided with a hollow. stern or shank 41, which isadaptedto be inserted through a hole in the cover band fitted over theend of the shaft 33, which latter is provided with a longitudinallyeirtended slot d2, into which passes a cross pin 43 within the hollowShank or stem 41, and by means of which the handle is engaged with theshaftso as to rotate the saine when the handle vis turned. The studs 23,2e which carry the terminal screws 2l, 22 are insulated :from the crossbar 25 by strips 43 sulatedy flexible `conductors 44:, 45 to fixedterminals 46, 47 extended through the back wall of the casing and havingconnected vof of micaor other-Suitable insulating material.4

The studs 23, 24 are connected by in- 90 therewith eontinuations ofthewires 44, 45,

which form part of two circuits containing tact with the terminai screws21, 22.

Tlievcontaot arm 20 is common rto both..v

circuits, which are diagrammatically shown' is connected b the Wire 54,and with the other .of wliie are connected by the wires 4i, 45.

eleotromagnets .50, 5l are provided with the electromagnets 50, 51...vvThe wire 54is electrically connected with the ,Contact arm 20, throughthe metal frame .or

ica

I two electromagnets 50, 51, which are enerlgired when the contact arm20 makes conin Fig.- 6, und comprises line wires 52, 53, with one ofwhich as .52 the contact arm 20,

suitable armatures 57, 58, which are operatively connected in a mannerwell understood, with ,the mechanism (not shown) -which operates thedamper Vor other devices to be controlled. l

` The glass disk d Ais broken away as at 60, Fig. 3, so as not tointerfere with the handle 40 In operation with thelinstrument hereinshown, the handle 40 is turned so as to move the pointer 27 to thegraduation g on the dial,- which-is indicative ofthe temperature atwhich it ,is desired the house or other' building or a 'room thereinshould be heated.

The screws 2l, 22 are adjusted 'at the factory with relation to thecontact arm 20,`

so that the temperature may vary' one or more de rees on either side ofthe degree with which the pointer registers. When the temperature invthe vicinity of the instrunient rises above that at which the pointerrests, a sufiicient amount, say one or two de grecs, the contact arm 20is brought into contact with the screw 21 and the circuit of .themagnet-44; is closed, therebyk eneru gizing vthe said magnet andoperating the mechanism (not shown) to close the damper.

When the temperature of the room-falls below the desired temperature,say one or two vaoy degrees, the contact arm 2O is brought into Icontactwith the. screw 22 and the circuit of the magnet 45 lis closed, whichenergizes the same and eil'ects the opening of the damper. It will beobserved that the pointer 27,

l Tshaped bar 26 and toothed disk or gear 30 may be and preferably aremade in one piece of metal, and may be stamped out o f av piece of sheetmetal, which vserves to s1mi plify and reduce the cost of theinstrument.

So also it will be observed` that the convolutions of the-thermostaticstrip are concentric, which enables the thermostat to be brought intoclose proximity to the disk e vand thereby enables the instrument to becontained in a vshallow* casing, which serves to make theinstrumentcompact and also to reduce the cost.

By making the handle detachablefrom shaft' 33', li ability of thepointer being turned byfunauthorized per'sonsisA reduced to a zInininfiu'rn.

'Claim'sz i y l. In an instrument of the class described, incombination, a casing, provided with a .removable cover having anopening in it,

to said plate, a shaft supported by said cross bar `and plate andVextended through said disk, ,a 'thermostatic strip having 'a plu'rality of concentric convolutions located between said plate and crossbar and having one end secured to said shaft, 'a contact arm mounted' onsaid shaft in front of said disk, circuit terminals between which saidcontact arm is extended, a T-shaped carrier for said terminals havingthe latter secured to ,the cross bar of said carrier, a pointer integralwith the said carrier and coperating'with said graduations, and atoothed disk integral with said carrier, a pinion in mesh with saidltoothed disk, a shaft on which said pinion is mounted, anda handle onsaid shaft to turn it, substantially as described. l 4, 2. In aninstrument of the class described, in combination, circuit terminalsspaced apart, a T-shaped carrier for said terminals having the lattersecured to the cross bar of ,said carrier, a pointer extended from saidcross bar and integral therewith, a toothed disk integral with thevertical member of se f said carrier, means to rotate' said tootheddisk, a, hub on which said disk is mounted, a shaft extendedthrough saidhub, a contact arm attached to one end of said shaft and having its freeend extended' between said circuit terminals, and a thermostat confnected with said shaft to yrotate the same and move said-contact arm,substantiallyas described.

" In testimony whereof, I havesigned my name to this specification inthe presence of two subscribing witnesses. ,l

GEORGE E. SPEAR. Vitnessesz E. M. Renn, 'FRED D. HAG'AR.'

